1. Field of the Invention
The present invention relates to the pivoting apparatus of an industrial robot, and more particularly to wiring and processing cables in a pipe member that is inserted with play into a hollow provided through a speed reducer, a motor, and an encoder.
2. Description of the Related Art
A conventional pivoting apparatus of a conventional industrial robot will be explained referring to Japanese Laid-Open Publication No. 1993-57664. According to Japanese Laid-Open Publication No. 1993-57664, a pivoting apparatus includes a fixed base of a robot, a pivoting body being pivotably coupled to the fixed base, a moving mechanism portion, such as a robot arm coupled to the surface of the pivoting body, a motor for pivotably driving the pivoting body, and a speed reducer for transferring an output of the motor to the pivoting body; cables for supplying driving mechanism portion, such as a robot arm, with electric power or the like, are disposed through a protection pipe that passes through hollows of the motor and the speed reducer, by forming hollows along the center axes of the motor and the speed reducer and arranging the center axes coaxially with each other, and by arranging the center axes of the motor and the speed reducer coaxially with the pivotal center axis of the pivoting body.
In the pivoting apparatus of the industrial robot constituted as described above, by forming hollows along the center axes of the motor and the speed reducer and arranging the center axes coaxially with each other, by arranging the center axes of the motor and the speed reducer coaxially with the pivotal center axis of the pivoting body, and by disposing the cables so as to pass through the hollows of the motor and the speed reducer, the cables pass along the center axis of the pivoting body, thereby eliminating friction with the housing or the fixed base; therefore, breaking of wires due to wear and tear can be eliminated.
However, in the pivoting apparatus of the industrial robot described above, there has been a problem in that, with increased information and the like for driving and controlling the arm or the like, thereby upsizing the bundle of the cables, pivoting of the protection pipe along with the motor shaft could damage the coatings of the cables.